20 resultados para Synthetic and natural cannabinoids


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The main purpose of the present doctoral thesis is to investigate subjective experiences and cognitive processes in four different types of altered states of consciousness: naturally occurring dreaming, cognitively induced hypnosis, pharmacologically induced sedation, and pathological psychosis. Both empirical and theoretical research is carried out, resulting in four empirical and four theoretical studies. The thesis begins with a review of the main concepts used in consciousness research, the most influential philosophical and neurobiological theories of subjective experience, the classification of altered states of consciousness, and the main empirical methods used to study consciousness alterations. Next, findings of the original studies are discussed, as follows. Phenomenal consciousness is found to be dissociable from responsiveness, as subjective experiences do occur in unresponsive states, including anaesthetic-induced sedation and natural sleep, as demonstrated by post-awakening subjective reports. Two new tools for the content analysis of subjective experiences and dreams are presented, focusing on the diversity, complexity and dynamics of phenomenal consciousness. In addition, a new experimental paradigm of serial awakenings from non-rapid eye movement sleep is introduced, which enables more rapid sampling of dream reports than has been available in previous studies. It is also suggested that lucid dreaming can be studied using transcranial brain stimulation techniques and systematic analysis of pre-lucid dreaming. For blind judges, dreams of psychotic patients appear to be indistinguishable from waking mentation reports collected from the same patients, which indicates a close resemblance of these states of mind. However, despite phenomenological similarities, dreaming should not be treated as a uniform research model of psychotic or intact consciousness. Contrary to this, there seems to be a multiplicity of routes of how different states of consciousness can be associated. For instance, seemingly identical time perception distortions in different alterations of consciousness may have diverse underlying causes for these distortions. It is also shown that altered states do not necessarily exhibit impaired cognitive processing compared to a baseline waking state of consciousness: a case study of time perception in a hypnotic virtuoso indicates a more consistent perceptual timing under hypnosis than in a waking state. The thesis ends with a brief discussion of the most promising new perspectives for the study of alterations of consciousness.

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In recent years, there have been studies that show a correlation between the hyperactivity of children and use of artificial food additives, including colorants. This has, in part, led to preference of natural products over products with artificial additives. Consumers have also become more aware of health issues. Natural food colorants have many bioactive functions, mainly vitamin A activity of carotenoids and antioxidativity, and therefore they could be more easily accepted by the consumers. However, natural colorant compounds are usually unstable, which restricts their usage. Microencapsulation could be one way to enhance the stability of natural colorant compounds and thus enable better usage for them as food colorants. Microencapsulation is a term used for processes in which the active material is totally enveloped in a coating or capsule, and thus it is separated and protected from the surrounding environment. In addition to protection by the capsule, microencapsulation can also be used to modify solubility and other properties of the encapsulated material, for example, to incorporate fat-soluble compounds into aqueous matrices. The aim of this thesis work was to study the stability of two natural pigments, lutein (carotenoid) and betanin (betalain), and to determine possible ways to enhance their stability with different microencapsulation techniques. Another aim was the extraction of pigments without the use of organic solvents and the development of previously used extraction methods. Stability of pigments in microencapsulated pigment preparations and model foods containing these were studied by measuring the pigment content after storage in different conditions. Preliminary studies on the bioavailability of microencapsulated pigments and sensory evaluation for consumer acceptance of model foods containing microencapsulated pigments were also carried out. Enzyme-assisted oil extraction was used to extract lutein from marigold (Tagetes erecta) flower without organic solvents, and the yield was comparable to solvent extraction of lutein from the same flowers. The effects of temperature, extraction time, and beet:water ratio on extraction efficiency of betanin from red beet (Beta vulgaris) were studied and the optimal conditions for maximum yield and maximum betanin concentration were determined. In both cases, extraction at 40 °C was better than extraction at 80 °C and the extraction for five minutes was as efficient as 15 or 30 minutes. For maximum betanin yield, the beet:water ratio of 1:2 was better, with possibly repeated extraction, but for maximum betanin concentration, a ratio of 1:1 was better. Lutein was incorporated into oil-in-water (o/w) emulsions with a polar oil fraction from oat (Avena sativa) as an emulsifier and mixtures of guar gum and xanthan gum or locust bean gum and xanthan gum as stabilizers to retard creaming. The stability of lutein in these emulsions was quite good, with 77 to 91 percent of lutein being left after storage in the dark at 20 to 22°C for 10 weeks whereas in spray dried emulsions the retention of lutein was 67 to 75 percent. The retention of lutein in oil was also good at 85 percent. Betanin was incorporated into the inner w1 water phase of a water1-in-oil-inwater2 (w1/o/w2) double emulsion with primary w1/o emulsion droplet size of 0.34 μm and secondary w1/o/w2 emulsion droplet size of 5.5 μm and encapsulation efficiency of betanin of 89 percent. In vitro intestinal lipid digestion was performed on the double emulsion, and during the first two hours, coalescence of the inner water phase droplets was observed, and the sizes of the double emulsion droplets increased quickly because of aggregation. This period also corresponded to gradual release of betanin, with a final release of 35 percent. The double emulsion structure was retained throughout the three-hour experiment. Betanin was also spray dried and incorporated into model juices with different pH and dry matter content. Model juices were stored in the dark at -20, 4, 20–24 or 60 °C (accelerated test) for several months. Betanin degraded quite rapidly in all of the samples and higher temperature and a lower pH accelerated degradation. Stability of betanin was much better in the spray dried powder, with practically no degradation during six months of storage in the dark at 20 to 24 °C and good stability also for six months in the dark at 60 °C with 60 percent retention. Consumer acceptance of model juices colored with spray dried betanin was compared with similar model juices colored with anthocyanins or beet extract. Consumers preferred beet extract and anthocyanin colored model juices over juices colored with spray dried betanin. However, spray dried betanin did not impart any off-odors or off-flavors into the model juices contrary to the beet extract. In conclusion, this thesis describes novel solvent-free extraction and encapsulation processes for lutein and betanin from plant sources. Lutein showed good stability in oil and in o/w emulsions, but slightly inferior in spray dried emulsions. In vitro intestinal lipid digestion showed a good stability of w1/o/w2 double emulsion and quite high retention of betanin during digestion. Consumer acceptance of model juices colored with spray dried betanin was not as good as model juices colored with anthocyanins, but addition of betanin to real berry juice could produce better results with mixture of added betanin and natural berry anthocyanins could produce a more acceptable color. Overall, further studies are needed to obtain natural colorants with good stability for the use in food products.

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Tämän kandidaatintyön aiheena oli löytää biojalostamon näkökulmasta käyttökelpoisia tuotantoreittejä puuperäisistä materiaaleista bioperäisiin kemikaaleihin, joilla olisi mahdollista korvata synteettisiä sideaineita. Tällä hetkellä suurin osa sideaineista ja päällystemateriaaleista tuotetaan uusiutumattomista luonnonvaroista, kuten maakaasusta ja öljystä. Lopputuotteiden kierrätettävyyden ja vihreyden ohella yksi metsäteollisuuden tulevaisuuden trendejä on pyrkiä irti öljy- ja maakaasuriippuvuudesta. Muutoksella voidaan säästää sekä ympäristöä, että rahaa. Biopohjaisilla drop-in kemikaaleilla ja muilla biopohjaisilla vaihtoehdoilla tämä on mahdollista Tässä työssä tutkittiin ja havainnollistettiin mahdollisin tuotantoreitein useiden tällä hetkellä käytössä olevien sideaineiden korvaamista biopohjaisilla versioilla. Työ tehtiin kirjallisuustutkielmana, eikä siihen kuulunut laboratoriokokeita. Työn ensimmäisessä osassa painopiste on biojalostamossa ja dispersiopäällystyksessä. Toisessa osassa esitellään tällä hetkellä käytettyjä sideaineita ja niiden mahdollisia biopohjaisia korvaajia tuotantoreitteineen. Työn toissijainen tarkoitus oli selvittää lyhyesti mitä muita puuperäisiä komponentteja voidaan käyttää suoraan paperin ja kartongin päällystämiseen. Viimeiseksi on esitelty vielä lyhyesti kaupallisesti käytössä olevia biomuoveja ja päällysteitä.

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Subshifts are sets of configurations over an infinite grid defined by a set of forbidden patterns. In this thesis, we study two-dimensional subshifts offinite type (2D SFTs), where the underlying grid is Z2 and the set of for-bidden patterns is finite. We are mainly interested in the interplay between the computational power of 2D SFTs and their geometry, examined through the concept of expansive subdynamics. 2D SFTs with expansive directions form an interesting and natural class of subshifts that lie between dimensions 1 and 2. An SFT that has only one non-expansive direction is called extremely expansive. We prove that in many aspects, extremely expansive 2D SFTs display the totality of behaviours of general 2D SFTs. For example, we construct an aperiodic extremely expansive 2D SFT and we prove that the emptiness problem is undecidable even when restricted to the class of extremely expansive 2D SFTs. We also prove that every Medvedev class contains an extremely expansive 2D SFT and we provide a characterization of the sets of directions that can be the set of non-expansive directions of a 2D SFT. Finally, we prove that for every computable sequence of 2D SFTs with an expansive direction, there exists a universal object that simulates all of the elements of the sequence. We use the so called hierarchical, self-simulating or fixed-point method for constructing 2D SFTs which has been previously used by Ga´cs, Durand, Romashchenko and Shen.

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Globalization and the developments of supply chain have made inexpensive labor and the low production costs of developing countries available to businesses worldwide. Unfortunately, these developments have also led to the exploitation of human and natural resources. The increasing supply of cheap and fashionable clothing has created a contradiction between consumers’ concerns for sustainability and their purchase behavior in the fashion industry. Since the uncovering of several sweatshop scandals in the 1980’s and 1990’s ethical fashion brands have started to emerge. Ethical fashion has sparked the interest of consumers and studies have shown promising positive attitudes towards it. However, these attitudes have failed to translate into action and purchase behavior of ethical fashion has not reached the expectations. In order to translate the positive attitudes into buying companies must understand consumer’s motivations and reasons behind the purchase decision. The objective of this study is to understand the antecedents behind young consumer’s purchase intention of ethical fashion. The study is based on the theory of planned behavior which has been widely used to study consumer behavior and purchase decisions. The theory has also been used in ethical decision-making and fashion context before. According to the theory, in order to understand purchase intentions consumer’s attitudes toward buying ethical fashion were studied. The theory also states that attitudes are formed from beliefs, thus, consumer’s beliefs about the fashion industry were studied. To contribute to existing research, the effect of sweatshop issues and environmental issues were compared. The data was collected from university students (n=617) with an online survey. The results were analyzed by statistical methods and they revealed that young Finnish consumers hold positive attitudes towards buying ethical fashion as well as positive purchase intentions of ethical fashion. A strong relationship was found between positive attitudes and positive purchase intentions. Also, the more negative consumers’ beliefs of the fashion industry were the more positive their attitudes toward buying ethical fashion were. In contradiction to previous research this study revealed that environmental issues had greater effect on attitudes than sweatshop issues. Interesting differences between consumers were found depending on their field of education. Students from humanities and social sciences held the most negative beliefs as well as most positive attitudes and purchase intentions of ethical fashion.